Projectile



PROJECTILE Filed May 15, 1924 INVENTOR I XI .VQW

ATTORNEY Patented Jan. 7, 1930 PIETER DANIEL VAN ESSEN, OF THE HAGUE, NETHERLANDS PROJECTILE Application filed May 15, 1924. Serial No. 713,513.

The use of trench mortars, infantry howitzers and similar articles of ordnance, combining the features of extreme mobility and the ability to fire high capacity projectiles at 5 low range, have introduced new conditions in the supply of ordnance material suitable for this purpose. The chief requirements in regard to projectiles adapted for use in ordnance of this description is a maximum explosive capacity compatible with light weight and low calibre. Owing to the comparatively small calibre of trench mortars, this requirement involves the use of thin walled containers and projectiles of extended length. At high angles of incidence, and

fused with instantaneous impact fuses, projectiles of extended length present certain advantages in that their zone of dispersion on fragmentation is a maximum, owing to the rearward protrusion from the ground of the main portion of the detonating charge, at the moment of impact. In this manner the localizing influence on the effect of detonation, due to irregularities in the ground is to a great extent overcome.

The difficulty hitherto has been to attain these advantages without unduly increasing the length of bore of the mortar and in consequence its weight. Furthermore, it has not been found practicable to reduce the thickness of the containing walls of the projectile, so as to increase their loading capacity, beyond well defined limits, dependent on the powder pressures in the gun and. their distribution on the base or the rearward portion of the projectile.

To meet these requirements I have invented. a projectile of such shape that the chamber pressure in the gun may be applied to a substantially large surface thereof, thus obviating the rearward thickening ofv the projectile walls customary in a projectile of normal design.

Another object of my invention is to provide a projectile adapted to be fired effectively under wide variations in the angle of elevation, without relying on its rotation about its axis to retain its position along the trajectory. Experience has shown that at high firing elevations rotating projectiles drift out of their normal position tangential to the trajectory; this deviation impairs the proper functioning of direct impact fuses and also results in a deepened dispersion zone and loss of concentration on the objective. The use of wind vanes, as a means of correction, is effective only at the expense of the remaining energy of the projectile. In the case of projectiles havin no initial rotation, forexample, those fired from smooth bore guns, the conditions are still more difficult. While admitting the virtues of having the center of gravity as far forward as possible, and the stabilizing influence of wind vanes and similar contriv- 6 ances, a further disturbing factor is introduced, viz: the influence of gas pressure immediately after the gas checking portion of the projectile has left the muzzle of the gun. Said pressure may cause a deviation of the axis of the projectile from its proper trajectory, which is the more aggravated by the fact that the projectile is not rotating. By my method of construction, I provide a projectile, substantially non-rotatable about its axis, having the known advantages of a forwardly placed center of gravity and corrective wind vanes, but by tapering the body of the projectile rearwardly and also providing centering means at the rear of said tapered body, I efiect a gradual release of gas pressure, while continuing to guide or center my projectile until said release has been substantially effected. By these means I am able to obtain accurate and effective firing even at high angles of elevation, and substantially reduce the depth of dispersion usual in ordnance of this type.

A further object of my invention is to provide a projectile, the firing of which from the gun will not be disclosed by a highly luminous flash; similarly I aim to reduce the report emitted on gun fire so that the exact position of the battery shall not be disclosed to the enemy.

A further object of my invention is to secure even fragmentation of the projectile walls on detonation of the charge and their projection or dispersion at high velocity over a wide area.

In the attached drawing, I show in Fig. 1 a longitudinal section of my projectile, in Fig. 2 a side elevation and in Fig. 3 a rear end elevation.

In Fig. 1 of the drawing, I show a projectile consisting of ashort ogival head A, adapted to receive an impact fuse Bqf known design, andhaving a cavity C to belfille d with a high explosive. Rearwardly the head A is reduced as to its diameter andfs'ui'tably" threaded at D. 1'show"ai'h011 "w explosive containing body E, tapered rearwardly,

ing a forward portion adapted to engage with the rearward portion Dtof the headA, and

having a rearward portion adapted toengage it h h ward pe ttihh 10i? he ail 1 .1899

' G. Said flail piecejG-isofhollowjconstruq 11 Pr amass.

i an is a ered. Xter a -yfmm the d m.- tr t ear rde ehii y Qifihhp body Qa f hfiea l rwith heta-i pie e .6 I show four wings or vanesI-I, set longitudi ma and at right angles to; each other, in

thickness s t si re ihs utw rdly h r elled rearwardly, and blended forwardly to a e eih hQPIEE F-K Q whit projectileS p d h ih b ee h oad ng. shes said vaneshave bearing points J, forined by slhhll lateral i -hi etiohs the Yeas, he diameter of the varies over; these projections is ght y grea r h' h mhh h ore o h Pr t le; a-p ht K mme ia ly' forward of the tapering body E, also acts a, centering band, as long as the head A is in the bore of the gun.

In the caseof projectiles adapted ,for muz;

, zle loa ding the use iof the deformable projections on' theyanes are not essential, nd, 1th an s T ma be 9 h t d h a Pe i r l ed e-a .Slihhhl hi b r .of the v p u I of the forward sectlo By t'fs construction it ;is evident that the ah f erasur ii hh shah appli a o e; major" part of the eirternal surface, of the,

projectile, foregrample, theentire the body E and the tail piece JG, thhsjyjermith s th w ls t t p' ie' il e pp i d:

b thi mfil h "We be 'p he ib e by he convention l oh tnis iqhf o p oje i er inv he was or .ig ian rv thicknes lie is rwyii lejcl asiggu s hens a a g or sh i h he.

dering portion of the projectile at its maximum diameter, aflords a gradual release of the chamber pressure, as soon as said shouldering portion is free of the muzzle of the gun, and While the rearward portion of the projectile is still kept centered in the gun. In this manner, I avoid erratic deviation of the projectileat the colnmencernent of its trajectory. These important advantages are attained, in addition to those known to result fr'oin' the use'of wind arrested a center of gravity disposed as forwardly as possible. Furthermore, the profile of my projectile body issuChast aYOid the formation on impact anddetofnation of any elongated fragments, butto attain an. even fragmentation with a Wide dispersion of the said fragments athigh velocity. V 7

From the foregoing, ithwill be apparent that vI have devised a. projectile suitable for hi Sn hth'be 'e s ih that th Pr je t l s accurately centered in its loaded {position as Well as during its travel along the gun bore and the propellant pressure is'gradually released as the projectile reachesthe muzzle.

Havi g s i bel th i v n i n. W a I claim as new and desire, to secure by Letters Patent is; I

In a trench mortar-proj ectile the combination of, a short ogiy'al-head:blending rear.- wardly withia portion adaptedto fit the muzzle of the-mortar, substantially elongated h or i l ad? ph bn tt hhed a wa d f ehead, a ni l mi p rtion ing wind, vanes extending to fitthe'mu'zzle of the mortar, all of said; portionsbeing chambered to receive explosive, and presenting in flight an extendedstream line surfacesubstantially uninterrupted except by the vanes extending. ther efroni, V I V Intestimony whereofI-ghereuhtO g hh liht is 3th d y fn W IQ- L RIETER; DANIEL VAN ESSE-N. 

